54 confirmed waterborne leptospirosis cases, four deaths in Brazil's Rio Grande do Sul state after floods.

400-character summary: Brazil's Rio Grande do Sul state saw 54 confirmed cases of waterborne leptospirosis, leading to four deaths after unprecedented floods in April-May. 800 suspected cases are under investigation, while 165 people were killed in the floods, affecting over 2.3 million Brazilians. The government declared it a "climate disaster", with 581,000 displaced and 55,000 Gauchos housed temporarily. Many cities are still underwater.